Any ideas how to increase the volume with a raspiaudio device?

I purchased this device for $15:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

And I cannot seem to find a way with picoreplayer 5.0.0 to boost the audio output of this i2s device. This seemed like a similar post:

https://www.raspberrypi.org/forums/v...c.php?t=181106

But couldn't get any of that working. I am using a Topping TP21 for output which has 25 WPC. I'm wishing I could find some way to use amixer to increase the output. I've tried all the various hifiberry pull down options for output devices in picoreplayer and only two work for me. The DAC Zero/MiniAmp and the Dac+ Light . So it's not I think that I'm setting the wrong device.

Justin